trivial: update content model example in README.md
diff --git a/README.md b/README.md
index d2bac00..ad6adc9 100644
--- a/README.md
+++ b/README.md
@@ -63,6 +63,7 @@
 https://site.ch/de-ch.sitemap-index.xml
 https://site.ch/de-ch.sitemap.xml
 https://site.ch/de-ch.sitemap.products-sitemap.xml
+https://site.ch/fr-ch.sitemap-index.xml
 https://site.ch/fr-ch.sitemap.xml
 ```